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Enhanced Equidistant Chosen Message Power Analysis of RSA-CRT Algorithm (RSA-CRT의 향상된 등간격 선택 평문 전력 분석)

  • Park, Jong-Yeon;Han, Dong-Guk;Yi, Ok-Yeon;Choi, Doo-Ho
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.48 no.2
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    • pp.117-126
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    • 2011
  • RSA-CRT algorithm is widely used to improve the performance of RSA algorithm. However, it is also vulnerable to side channel attacks like as general RSA. One of the power attacks on RSA-CRT, proposed by Boer et al., is a power analysis which utilizes reduction steps of RSA-CRT algorithm with equidistant chosen messages, called as ECMPA(Equidistant Chosen Messages Power Analysis) or MRED(Modular Reduction on Equidistant Data) analysis. This method is to find reduction output value r=xmodp which has the same equidistant patterns as equidistant messages. One can easily compute secret prime p from exposure of r. However, the result of analysis from a reduction step in [5] is remarkably different in our experiment from what Boer expected in [5]. Especially, we found that there are Ghost key patterns depending on the selection of attack bits and selected reduction algorithms. Thus, in this paper we propose several Ghost key patterns unknown to us until now, then we suggest enhanced and detailed analyzing methods.

Transcript accumulation of carotenoid biosynthesis genes in the cyanobacterium Synechocystis sp. PCC 6803 during the dark-to-light transition is mediated by photosynthetic electron transport

  • Ryu, Jee-Youn;Song, Ji-Young;Chung, Young-Ho;Park, Young-Mok;Chow, Wah-Soon;Park, Youn-Il
    • Plant Biotechnology Reports
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    • v.4 no.2
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    • pp.149-155
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    • 2010
  • Expression of the genes for carotenoid bio-synthesis (crt) is dependent on light, but little is known about the underlying mechanism of light sensing and signalling in the cyanobacterium Synechocystis sp. PCC 6803 (hereafter, Synechocystis). In the present study, we investigated the light-induced increase in the transcript levels of Synechocystis crt genes, including phytoene synthase (crtB), phytoene desaturase (crtP), ${\zeta}$-carotene desaturase (crtQ), and ${\beta}$-carotene hydroxylase (crtR), during a darkto-light transition period. During the dark-to-light shift, the increase in the crt transcript levels was not affected by mutations in cyanobacterial photoreceptors, such as phytochromes (cph1, cph2 and cph3) and a cryptochrome-type photoreceptor (ccry), or respiratory electron transport components NDH and Cyd/CtaI. However, treatment with photosynthetic electron transport inhibitors significantly diminished the accumulation of crt gene transcripts. Therefore, the light induction of the Synechocystis crt gene expression is most likely mediated by photosynthetic electron transport rather than by cyanobacterial photoreceptors during the dark-to-light transition.

PET/CT planning during chemoradiotherapy for esophageal cancer

  • Seol, Ki Ho;Lee, Jeong Eun
    • Radiation Oncology Journal
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    • v.32 no.1
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    • pp.31-42
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    • 2014
  • Purpose: To evaluate the usefulness of positron emission tomography/computed tomography (PET/CT) for field modification during radiotherapy in esophageal cancer. Materials and Methods: We conducted a retrospective study on 33 patients that underwent chemoradiotherapy (CRT). Pathologic findings were squamous cell carcinoma in 32 patients and adenocarcinoma in 1 patient. All patients underwent PET/CT scans before and during CRT (after receiving 40 Gy and before a 20 Gy boost dose). Response evaluation was determined by PET/CT using metabolic tumor volume (MTV), total glycolytic activity (TGA), MTV ratio (rMTV) and TGA ratio (rTGA), or determined by CT. rMTV and rTGA were reduction ratio of MTV and TGA between before and during CRT, respectively. Results: Significant decreases in MTV ($MTV_{2.5}$: mean 70.09%, p < 0.001) and TGA ($TGAV_{2.5}$: mean 79.08%, p < 0.001) were found between before and during CRT. Median $rMTV_{2.5}$ was 0.299 (range, 0 to 0.98) and median $rTGAV_{2.5}$ was 0.209 (range, 0 to 0.92). During CRT, PET/CT detected newly developed distant metastasis in 1 patient, and this resulted in a treatment strategy change. At a median 4 months (range, 0 to 12 months) after completion of CRT, 8 patients (24.2%) achieved clinically complete response, 11 (33.3%) partial response, 5 (15.2%) stable disease, and 9 (27.3%) disease progression. $SUV_{max}$ (p = 0.029), $rMTV_{50%}$ (p = 0.016), $rMTV_{75%}$ (p = 0.023) on intra-treatment PET were found to correlate with complete clinical response. Conclusion: PET/CT during CRT can provide additional information useful for radiotherapy planning and offer the potential for tumor response evaluation during CRT. $rMTV_{50%}$ during CRT was found to be a useful predictor of clinical response.

An Improved Side Channel Attack Using Event Information of Subtraction (뺄셈연산의 이벤트 정보를 활용한 향상된 RSA-CRT 부채널분석공격 방법)

  • Park, Jong-Yeon;Han, Dong-Guk;Yi, Okyeon;Kim, Jung-Nyeo
    • KIPS Transactions on Computer and Communication Systems
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    • v.2 no.2
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    • pp.83-92
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    • 2013
  • RSA-CRT is a widely used algorithm that provides high performance implementation of the RSA-signature algorithm. Many previous studies on each operation step have been published to verify the physical leakages of RSA-CRT when used in smart devices. This paper proposes SAED (subtraction algorithm analysis on equidistant data), which extracts sensitive information using the event information of the subtraction operation in a reduction algorithm. SAED is an attack method that uses algorithm-dependent power signal changes. An adversary can extract a key using differential power analysis (DPA) of the subtraction operation. This paper indicates the theoretical rationality of SAED, and shows that its results are better than those of other methods. According to our experiments, only 256 power traces are sufficient to acquire one block of data. We verify that this method is more efficient than those proposed in previously published studies.

Timing of Esophagectomy after Neoadjuvant Chemoradiation Therapy Affects the Incidence of Anastomotic Leaks

  • Roh, Simon;Iannettoni, Mark D.;Keech, John;Arshava, Evgeny V.;Swatek, Anthony;Zimmerman, Miriam B.;Weigel, Ronald J.;Parekh, Kalpaj R.
    • Journal of Chest Surgery
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    • v.52 no.1
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    • pp.1-8
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    • 2019
  • Background: Neoadjuvant chemoradiation therapy (nCRT) has become the standard of care for esophageal cancer patients prior to esophagectomy. However, the optimal timing for surgery after completion of nCRT remains unclear. Methods: A retrospective review was performed of patients who underwent esophagectomy with cervical anastomosis for esophageal cancer at a single institution between January 2000 and June 2015. Patients were categorized into 3 cohorts: those who did not receive nCRT prior to esophagectomy (no nCRT), those who underwent esophagectomy within 35 days after nCRT (${\leq}35d$), and those who underwent esophagectomy more than 35 days after nCRT (>35d). Results: A total of 366 esophagectomies were performed during the study period, and 348 patients met the inclusion criteria. Anastomotic leaks occurred in 11.8% of all patients included in the study (41 of 348). Within each cohort, anastomotic leaks were detected in 14.7% of patients (17 of 116) in the no nCRT cohort, 7.3% (13 of 177) in the ${\leq}35d$ cohort, and 20.0% (11 of 55) in the >35d cohort (p=0.020). Significant differences in the occurrence of anastomotic leaks were observed between the no nCRT and ${\leq}35d$ cohorts (p=0.044), and between the ${\leq}35d$ and >35d cohorts (p=0.007). Conclusion: Esophagectomy with cervical anastomosis within 35 days of nCRT resulted in a lower percentage of anastomotic leaks.

Partial Key Exposure Attack on Unbalanced RSA with small CRT exponent (작은 CRT 지수를 사용한 RSA에서의 일부 키 노출 공격)

  • 이희정
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.14 no.5
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    • pp.135-140
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    • 2004
  • In Crypto 2002 May analyzed the relation between the size of two primes and private key in unbalanced RSA with small CRT exponent. Also in Crypto 2003 he showed that if $N^{1}$4/ amount of most significant bits(least significant bits) of $d_{p}$ is exposed in balanced RSA with CRT, N can be factored. To prove this he used Howgrave-Graham's Theorem. In this paper we show that if $N^{1}$4/ amount of $d_{p}$ , p is smaller than q, and bigger than $N^{0.382}$ to avoid May's attack, is exposed in unbalanced RSA with small CRT exponent, it is enough to expose $d_{p}$ . We use Coppersmith's theorem with unbalanced primes.

Early Efficacy of Endostar Combined with Chemoradiotherapy for Advanced Cervical Cancers

  • Ke, Qing-Hua;Zhou, Shi-Qiong;Huang, Min;Lei, Yong;Du, Wei;Yang, Ji-Yuan
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.3
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    • pp.923-926
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    • 2012
  • The aim of this study was to investigate the early outcome of Endostar combined with chemoradiotherapy for advanced cervical cancer. Fifty-two cases (FIGO IIb to IVa) were divided randomly into two groups, receiving chemoradiotherapy alone (CRT group) and Endostar combined with chemoradiotherapy (CRT+E group). For the patients in the CRT+E group, Endostar was administered daily with the dosage of 7.5 $mg/m^2$, and cisplatin was administered weekly with the dosage of 20 $mg/m^2$ during the radiation. The regimens lasted for 4 weeks with no difference in chemoradiotherapy between the two groups. The early outcome complete remission rate was 73.1%, partial remission rate was 23.1% and the total response rate was 96.2% in CRT+E group, a significant improvement on the 34.6%, 42.3% and 76.9%, respectively, in the CRT group. One year survive rates were 100% and 84.6% in the CRT+E group and CRT groups, the difference being significant. Endostar combined with chemoradiotherapy can improve the early outcome of the advanced cervical cancer, and adverse effects were not encountered.

Multiplier Using CRT and Overlapped Multiple-bit Scanning Method (CRT와 중첩다중비트 주사기법을 접목한 승산기)

  • 김우완;장상동
    • Journal of KIISE:Computer Systems and Theory
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    • v.30 no.12
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    • pp.749-755
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    • 2003
  • Digital signal processing hardware based in RNS is currently considered as an important method for high speed and low cost hardware realization. This research designs and implements the method for conversion from a specific residue number system with moduli of the from $(2^k-1, 2^k, 2^k+1)$ to a weighted number system. Then, it simulates the implementation using a overlapped multiple-bit scanning method in the process of CRT conversion. In conclusion, the simulation shows that the CRT method which is adopted in this research, performs arithmetic operations faster than the traditional approaches, due to advantages of parallel processing and carry-free arithmetic operation.

Genome sequence of carotenoid producing Sphingobacteriaceae bacterium SH-48 isolated from freshwater in Korea (카로티노이드 생산 Sphingobacteriaceae SH-48 균주의 유전체 염기서열 분석)

  • Choi, Ahyoung;Chung, Eu Jin;Nam, Young Ho;Choi, Gang-Guk
    • Korean Journal of Microbiology
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    • v.53 no.4
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    • pp.347-350
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    • 2017
  • We sequenced the genome of the Sphingobacteriaceae bacterium SH-48 isolated from the Sohan stream in Republic of Korea by using a dilution-to-extinction culturing method. The sequences were assembled into a draft genome containing 5,650,162 bp with a G + C content of 35.4% and 4,856 protein-coding genes in 2 contigs. This strain contains the carotenoid biosynthesis genes crtY, crtZ, crtD, crtI, crtB, and crtH as gene clusters. This genomic information provides new insights into the carotenoid biosynthesis pathway.

Chosen Message Attack on the RSA-CRT Countermeasure Based on Fault Propagation Method (오류 확산 기법에 기반한 RSA-CRT 대응책에 대한선택 메시지 공격)

  • Baek, Yi-Roo;Ha, Jae-Cheol
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.20 no.3
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    • pp.135-140
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    • 2010
  • The computation using Chinese Remainder Theorem in RSA cryptosystem is well suited in the digital signature or decryption processing due to its low computational load compared to the case of general RSA without CRT. Since the RSA-CRT algorithm is vulnerable to many fault insertion attacks, some countermeasures against them were proposed. Among several countermeasures, Yen et al. proposed two schemes based on fault propagation method. Unfortunately, a new vulnerability was founded in FDTC 2006 conference. To improve the original schemes, Kim et al. recently proposed a new countermeasure in which they adopt the AND operation for fault propagation. In this paper, we show that the proposed scheme using AND operation without checking procedure is also vulnerable to fault insertion attack with chosen messages.